Home & Garden Columns

About the House: A Do-It-Yourself Energy Audit

By Matt Cantor
Thursday July 23, 2009 - 10:10:00 AM

A few weeks ago, I made the dangerous trek out of Berkeley and into Contra Cost County. I took off my tie-dye, trimmed my mustache and put on dark glasses. True, the “Hate is not a family value” license plate holder was still visible but I parked far enough from the house to be safe. It was OK. We avoided politics. For all I know, they voted for Obama. Lots of people voted for Obama and, despite all my joking, they were actually very nice.  

The important things was that we had a common purpose. They were paying too much for electricity and I wanted to stop them from warming the globe. This being our common aim, we started unplugging away. 

Unplugging things is how we start when we want to understand how much power is being used for various things in the home. It’s a time-consuming process but the only way you’re really going to find out what’s making the meter spin is by unplugging or otherwise turning things off. That last part is a bit of a trick too, because just turning things off won’t completely stop them from drawing power. Many devices draw power even though they seem to be off. This can include computers and a host of computerized devices and almost anything that has a transformer or internal power supply. Lots of things like DVD players actually go onto a standby mode and don’t really power all the way off when you turn them off so to start this project, one has to actually unplug most things. If you want to do this, that’s what you’ll need to do. But I’m getting a little ahead of myself. The place we really want to begin is at your main electrical service. 

Every house has an electrical meter and a main disconnect. The first thing to do is to find yours. When you find the meter, you’ll notice that the meter has a disk that spins around. If everything is off, it won’t be turning at all but this is rare (unless you turn the main breaker off) so it should be moving a bit. In the case of our Contra Costa friends, it was moving so fast that I could barely track it. The method I’m going to show you doesn’t involve reading kilowatt hours, though that isn’t hard to do, but this is easier and actually very simple. It’s just a relative system. This way, you’ll know the relative expenditure of power and, thereby, where your biggest use (or biggest waste) lies. 

Start by turning off everything in the house. Again, it’s going to be best to unplug everything too, although many things like lamps and fans won’t require this. Electronics that have a constant low-level draw will still get a reading. In the case of my friends with the big bill, we chose not to turn off every single item since the usage that I read when these last “ghost” draws were still running was low enough to wash out of the equation. The point here is to figure out what makes up the lion’s share and where there’s room to trim fat. When you understand where the money and energy is going, it might change your behavior. That’s the idea. 

If you take a stopwatch, you can clock how long it takes for the disk in the middle of the meter to spin from one mark to the next. At high-usage levels this will be just a few seconds. If you want to use the fastest (lowest denomination) of the dials on the face of the meter, it’s the one on the far right, but this will take a long time for every test so I’d stick with the disk. 

Now, simply start testing various individual or grouped portions of the electrical system. Start by turning off everything but lighting. Turn on all the lights in the house and go read the meter. Write down the number of seconds it takes for the disk to spin this time. Now go back and turn on everything else in the house but have every light off. This is a big one (and was the lynch pin for our friends). Now try just the refrigerator (typically a very big user), then the TV, the stereo, the hot tub and every other thing you have. Remember that the only fair test will involve actually unplugging everything and plugging things in deliberately as you test your individual and group usage. If you take good notes, you should be able to make a good assessment of where, by percentage, the money and carbon is going. In the case of our friends, it turned out that, despite the two refrigerators and about a hundred other appliances, lighting was, by far, the biggest user. It accounted for roughly 80 percent of their use when we had everything turned on. Now, in fairness, they may have turned off half the lights some of the time but you know how humans are. We talk a good game but, when push comes to pummel, we want what we want and don’t bother me, I’m watching TV. Most people don’t go around turning things off. So….what shall we do? 

If, like my friends, you found that lighting was the biggest user in the house (do a fair test and turn them all on), you might want to take another revised look at the much-improved, LED and compact florescent lights (CFL) that one can find on the Internet or at more and more hardware stores. CFLs use about one quarter of the energy that incandescent lamps (including those little halogen ones) and LEDs use about one tenth. LEDs are currently quite expensive, but, given the fact that they may last a lifetime, think of the cost savings in bulbs as well as power. If you have bulbs that are hard to get to (top of that nasty stairwell), definitely go for one of the LED floods or whatever you’ll need to fit. LED’s are now available to fit low-voltage fixtures and pretty much any style you’ll need. They look odd (for now—I’m sure they’ll get better) and the color may not be right but we have to be flexible today. The earth is warming up and, if the bulb isn’t quite right, well think of it as part of the war effort and tighten your aesthetic belt, soldier. 

Keep in mind that older refrigerators and air conditioners are also big users and there are nice discounts today for Energy Star-rated appliances that can pay for themselves in a year or two. 

I believe that this sort of simple analysis, if taken to real action, can reduce your use by a large measure, perhaps 30 percent or more. Most of our waste is due to lack of attention and today, the payback may not simply be in a lower bill and a higher 401K, it may be in your grandchildren getting a chance to see a Polar Bear.